Nippon Electric Co., Ltd.

Nec Corporation

Toshio Ohkubo

Yuji Kajiwara

Hidehiko Katoh

Yasuhiro Otsuka

Michio Ishikawa

Tsutomu Itano

A film carrier is used for fabricating a semiconductor device, and comprises an insulating film and a plurality of conductive leads each extending on the insulating film and having a front side surface and a reverse side surface, and a bump is formed in each of the conductive leads and has a projecting surface projecting from the reverse side surface and a depressed surface defining a recess open to the front side surface, so that the bump has a dome-shaped configuration and is much liable to deform in a thermocompression bonding stage.

Process and apparatus for forming bumps on film carrier

A thermal printing head having a heating resistor prepared according to a thin-film technique and a wiring circuit prepared according to a thick-film technique achieves a high printing quality at a low cost. A thin-film resistor is formed on a heat-insulating dielectric layer which is, in turn, provided partially on a dielectric substrate, while thick-film lead electrodes, which are connected to a driving circuit, are formed on the dielectric substrate so as to make contact with the edge portion of the heat-insulating dielectric layer. Thin-film lead electrodes electrically connect the thick-film lead electrodes to the opposite ends of the thin-film resistor. The heat-insulating dielectric layer and the thick-film lead electrodes are provided by means of thick-film technique such as screen-printing and succeeding firing processes and the thin-film resistor and the thin-film lead electrodes are formed through thin-film technique such as sputtering or vacuum-evaporating process.

Integrated thermal printing head and method of manufacturing the same

Method of manufacturing an integrated thermal printing head

A thermal printing head which effects printing on thermally sensitive paper with Joule's heat generated by passing a current through a thick-film resistor is featured by the surface configuration of the thick-film resistor. In a cross-section perpendicular to the direction of the current passing through the resistor, the resistor is formed in such shape that the center portion is lower than the opposite edge portions. Owing to such concave top surface, despite of the fact that the heating resistor is a thick-film resistor, printing of high quality that is compatible to printing quality by a thin-film resistor can be accomplished. A practically useful thermal head having the resistors with the concave top surface can be realized through the photo-resist pattern technique combined with the screen printing technique.

Thick-film thermal printing head and method of manufacturing the same

Growing community of inventors

Tokyo, Japan

Toshio Ohkubo